silence a couple of unused-variable warnings
specify latin-1 as external format for read-whole-file

  The current implementation assumes a single-byte-per-char format;
  make that explicit.
add partial support for destructuring in macro-lambda-lists

  Fake it via DESTRUCTURING-BIND.
add not-entirely-correct VECTOR-PUSH-EXTEND
export FIND
make FIND and REPLACE work on vectors as well
add smoketests for FIND and REPLACE